I’m not going to tell anyone what to do with their bike, however, I will throw a couple things out there to consider…
1. Remove the clutch lever and inspect the pivot bushing.
If it is worn, loose, scored, or the hole has worn deeper, it will not engage the clutch correctly.
Also check to see if the rubber boot is torn, or jammed up inside the housing.
These alone can cause shifting issues.
2. Clutch fluid leaking out will never be seen on the floor, it will stick to the rear of the crankcase cover, IF the weep hole is clear and not clogged up (common)
3. Did you, or anyone else. Over fill the clutch master cylinder housing?
You don’t use the idiot lines outside by the window, you use the casting line inside the housing on the front wall.
Over filling can cause issues.
4. I would stop riding the bike you are unfamiliar with if you are hearing scraping, squeaking, or dragging noises from either wheel until it can be inspected by someone familiar with this model.
Everything you are describing sounds like a bike that has had the fluids neglected, and may have damaged the Clutch slave cylinder, and/or the left front brake caliper Secondary master cylinder assembly.